a. Field of the Invention
This invention relates generally to coverings for architectural openings and, more particularly, to an improved vane for use in such an architectural covering wherein the architectural covering might be a window blind, door blind, or other such covering used in the interior of a building structure.
b. Description of the Known Art
Coverings for architectural openings have been used for centuries to selectively cover doors, windows, archways and the like. Coverings have taken numerous forms such as draperies, various types of curtains as well as slatted coverings such as venetian blinds and vertical blinds. Vanes or slats utilized in horizontal and vertical slatted coverings also have taken numerous forms, with horizontal slats typically having different characteristics than vertical slats.
Slats used in horizontal slatted coverings must be somewhat rigid so as to not bend along their length whereby they will retain a horizontal orientation without sagging. Typical horizontal slats are made of wood, aluminum, plastic or the like and are generally flat planar bodies. They may, however, have a slight curvature to prevent them from bending or sagging along their length.
Vertical slatted blinds are becoming more popular and typically have a headrail that contains a carrier mechanism, a tilt rod, and a plurality of operatively interconnected vertical slats or vanes. The carrier mechanism includes a plurality of hangers for individually suspending the vertical vanes. The carrier mechanism is coupled to the tilt rod so that when the tilt rod is rotated about its longitudinal axis, the hangers are caused to rotate about vertical axes which, in turn, rotate the vertical vanes to which they are attached about the same axes. The vanes are always hung from their top edge with the hangers usually being undesirably visible or requiring a valance to cover them up.
Vanes for vertical slatted window blinds are typically made with one or more of four different types of materials. These materials are fabric, polyvinyl chloride (PVC), aluminum and wood. The most common vanes are made from either fabric, PVC, or a combination of fabric and PVC. Fabric vanes offer a very appealing softer appearance which adds quality to the finished look of the vane. It also provides a designer with a number of design choices regarding the type of fabric to use for a particular room. PVC vanes are plastic and, therefore, have a harder plastic appearance. One advantage of the PVC vane, however, is its strength. PVC vanes can be laminated or wrapped with fabric to provide the PVC strength with the fabric appearance.
There are disadvantages, however, to vanes made of fabric, PVC or combinations thereof. Vanes made solely of fabric are thin, and tend to twist along their length when rotated from the top edge. They, further, are substantially two dimensional. PVC vanes, which are typically flat and planar in structure, also tend to twist along their length when rotated from the top edge. The PVC vanes are normally thin even though they can be molded to provide a three-dimensional shape.
Several hybrids exist for fabric vertical vanes. For example, fabric vanes are often treated with a stiffener to impart structural rigidity. The stiffener takes away the fabric""s hand or softness but retains the look of the fabric. The vane will still twist, but less than non-treated fabric vanes. The treated fabric vanes also tend to curl in direct sunlight if the stiffener is not applied uniformly. Another hybrid, as mentioned previously, is a PVC vane laminated with the fabric. Such a vane has the structural strength and three dimensionality offered by a PVC vane with the appearance of a fabric vane. The fabric in this case also loses its hand or softness, however, and other problems common with PVC/fabric laminate vanes are that in sunlight, the fabric may curl and delaminate, there is increased assembly costs, the vanes are relatively heavy, and when the fabric is only laminated onto one face of the PVC, the reverse side is aesthetically displeasing. Another design includes a PVC vane core that is wrapped loosely with fabric. This provides a softer product with the fabric look, but it is very costly and difficult to fabricate. One other approach is a PVC vane with a groove along each edge so that a fabric insert can be positioned in and along the faces of the PVC vane. This approach is also costly, does not prevent longitudinal twisting and the reverse face in the grooved edges detracts from the fabric appearance. Another drawback with conventional vertical blind slats is that they typically have a cold appearance and do not simulate the softer and warmer look of curtains or draperies and this is to some degree due to the configuration of the slats.
Therefore, it is an object of the present invention to provide a new and improved vane for a window covering that will have a unique appearance when used horizontally, and will have the general appearance of a curtain when used vertically.
The vane of the present invention is contoured to provide a soft, drapery-like appearance when used in vertical coverings and to provide a new very distinct look when in horizontal coverings.
The slat in transverse cross-section is generally j-shaped having a main panel and a hook-shaped edge. The main panel has a shallow s-shaped cross-section and the hook-shaped edge is formed by folding one edge of a rectangular strip from which the slat is formed rearwardly upon itself. The edge which is folded rearwardly upon itself may form a smooth arcuate surface which may have a smaller radius of curvature than the radius of curvature of the s-shaped main panel. The folded edge, therefore, may simulate a pleat or fold in a curtain when the vane is suspended vertically and a smooth rounded edge of a slat when disposed horizontally. The radius of the folded edge can be varied to obtain different appearances and it does not necessarily have to be curved if different looks are desired.
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment, the appended claims, and the accompanying drawings.